Reference may be made to the following U.S. Patents of interest: Nos. 3,635,158; 3,808,657; 4,052,777; 3,594,255.
In offset printing, foreign material occasionally undesirably accumulates on the printing plate surface and is then impressed on the finished printed matter by the chain of printing rollers. These undesired foreign objects, known as "hickeys", can be removed by stopping the printing process and cleaning the printing plate with liquid commercially available for this purpose. In an attempt to avoid the printing operation shut-down, various printing roller structures, termed "hickey rollers", have been proposed for insertion in the printing roller chain to remove the undesired foreign objects by picking or whisking them off of the printing plate during the printing process.
One type hickey roller in past use employs a sleeve of leather over a rubber core. Some of the above-listed U.S. patents illustrate other proposed hickey rollers, which in general, suggest a multiple layer roller structure wherein a dense, felt fabric surface layer is applied over a printing roller rubber core. The felt surface is grinded to raise the compressed felt nap to aid in removing hickeys. Other proposed multiple layer hickey rollers involve depositing textile fibers by flocking onto the roller core surface.
It is now desired to provide an improved printing roller for removing hickeys, which improved roller more effectively removes hickeys and wherein the roller can be more readily cleaned than prior rollers. Also, it is desired to provide an improved method of making such a roller. Further, it is desired to provide an improved printing roller for use as a dampening roller.